Engines operating on gaseous fuels, such as natural gas, are commonly supplied with a lean fuel mixture, which is a mixture of air and fuel containing excess air beyond that which is stoichiometric for combustion. The lean fuel mixture often results in poor combustion such as misfires, incomplete combustion and poor fuel economy. Efforts to improve combustion result in detonation or the use of high energy spark which leads to short spark plug life. One factor that can lead to such events is the poor ability of conventional spark plugs to effectively and consistently ignite a lean fuel mixture in the cylinder of the operating engine.
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